Tolerance gauge for tapered threads



July 1 1924. v

B. M. W. HANSON TOLERANCE GUGE FOR TAPEBED THREADS Filed May 5. 192sPatented July 1, 1924.

Parana '.BENGT IVI. W. HANSQN, OF`HARTFORD, CONNECTICUT.

i TOLERANCE GAUGE FOR TAPERED THREADS.

Application sied May 5,

' To all 'whom t may concern.' Y

Be it known that I, BENGT M. .W. HAN- soN, a citizen of the UnitedStates, and a res- Vident of Hartford, countyl of Hartford, VState ofConnecticut, have invented certain new anduseful Improvements inTolerance Gauges for-Tapered Threads, of which following is aspecification.

This invention relates generally to measuring instruments and,; moreparticularly, to thread gauges. The device of the present thev Yinvention has various features of novelty.

and advantage susceptibleof use for testing thread members, but thesefeatures find peculiar adaptation in testing tapered threads,

' such as standard pipe threads, wherein the diameter of1 thethreadincreases from the endof the threaded member. Y

One object of the Yinvention is to provide an improvedv form of threadgauge fortesting tapered threads Yto indicate whether'the 'l thread willmeasure between certainvfixed 1 The invention accordingly consists inthe` features of construction, combination of elements and arrangementofparts which will be exemplified inthe construction hereinafter setforth, and the scope of the application of which will beindicated in theappended claims. .i Y, v

In the drawing forming apart of. this specification and in which thereis shown, by way of illustration only and not in a llimiting sense, atolerance gauge for pipe threads .embodyingi the'.features of my1nvention, l' K,

Fig. 1 is an elevation ofthe gauge Fig. 2 is a plan view; and i Fig. 3is a, detail view showing the jaw faces curved. l l I n Referring tothedrawing, the gauge comprises a body portion a onwhichare mount- 4 ,edthree lgauge.members b, 0 and 0l angularly spaced apart so that aproperly threaded end of a pipe may be inserted therebetween, thegaugemember @being adapted to supportthe pipe between theother two gaugememl has@ and d; and .the seus@ members b and i 1923. serial No.637,562. l

being arranged to contact at opposite sides with the pipe.

The gauge member c which is serrated on itscontact face, as at 10, isheld in a slot .11 in the body t by means of a screwl 12 extendingthrough. the body and threading into the gauge member c. The body a ispreferably counterbored as at 13 to receive the head of the screw 12.The gauge members Zi and d which are constructed similar to eachother,except that the serrated faces 14 and 15, respectively, areoppositelyinclined in accordance with the lead angle of the thread tofbegauged, are fastened, preferably rigidly, to the body a. Screws 17 whichthread into they body a, hold the gaugeA members b and Z from beinglifted from the slots 19 in the upper face of the body a, each of thegauge members being counter-bored as at 18 to accommodate. the headofthe screw. The openings or bores in thefmembers b and d are larger thanthe screws 17 so as to provide sufficient clearance for adjustment` ofthe gauge members. Eachgauge member is held .tightly against'vone wallof .the ,slot 19 by means of a pair of screws v20 which are .threadedthrough the. opposite wallof the.k

slot, vwhereby the gaugeV members are held `positively in positionagainst rotation or side movement.l To preventy end playfof the gauge'Vmembers b andrai, there are v'provided screws 21 which thread ,intok they body portion af just below the slot 19', vand the heads oftheselscrews are adapted to engage the endsv of the gauge members b iand d.Thus,

when the screws 17, 2O and :21 are all fastened tight, the gaugemembers'are positively held rigid, there being no: opportunity forsidewise, endwise, or up and down motion.

One ofthe gauge members, suchas d, is provided with graduations, as at22, 23 and 24;, by means of which the tolerance in the pipe being testedmay be indicated. For instance, if theend of Va pipe, which has beenaccurately threaded, be placed between the serrated faces lllvand 1,5,which converge toward the end at which the graduations 22, 23A and 24are located in accordance with the taper of the thread to be gauged, thethread vvon thek pipe will fit snuglywhen the end Vthread lies oppositethe-graduation 23.,y Tf

the thread is` of smaller diameter, then the 'pipel may bescrewed intothe gauge'tillthe ico tendsbeyond that point it is too small. If thethread is slightly larger than the desired diameter, it will beimpossible to screw the threaded pipe `up tothe graduation. In thiscase, if the thread can be screwed up to the graduation 22, it is withinthe permitted tolerance, but if not it is too large for the purposes athand. In other words, the end `of ithe pipe when screwed into the gaugemust be within'the graduations'ZQ vand24 to be withinY the prescribedtolerance. j

,'Referring toFig. 1, it will `be seenl that thegauge members and d donot lie-generally inthe same plane so as to contact ex- Iactly withdiametrically opposite points on the pipe inserted therebetween, butsuch points of contact are so disposed that slightly more than half thepipe ywill be within the gauge. Thus, when the pipe is screwed .wellinto the gauge, it is held against removalgat the threepoints of contacton the. serrated faces 10, 14 and 15; the two gauge vmembers b and alhold the pipe against the rest or gauge member c, and herefore the pipeis held or wedged .against movement in Vall directions.

If desired, the serrated faces 14 and 15 of Y the gauge members and d,respectively,

may be curvedto the curvature of the pipe thread being. measured. asshown in Fig. 3.

VBy the arrangement above described,

threaded pipes may be very quickly gauged.

. ,Because of the very flat angle vatrwhich the gauge members b and dare disposed to one another, the threaded end of a pipe may be insertedintoythe gauge from the top (Fig. 2) at a turn or two ahead. of itsfinal position vwhensc'rewed tightly into the gauge. provides a verymuch more convenient arfrangement than the ordinary ring gauge whichlhas been used for testing pipe threads, f sinceit is not necessary toscrew the pipe the entirelength of the gauge. 'By reason of the speedwith which pipe threadmeasurements maybe made, this form of gauge isfound to be very economical andv convenient.

y As before described, the gauge members l) and d are eachslidableslightly toward and away from each otheronaccount of theslightly larger bore of the hole through which the screwy 17 passes.This provides for a slight amount of adjustment so thatl `athreaded pipeinserted between the gauge members will be centered eXactlyabove thelcenter line vof the gauge member c.

`It is noted that, since the gauge lmen'ibers 15,40 and d areremovablefrom the body portion a, :they may lhe .replaced by Othersadapted to. measure smaller :ori larger .diam- -.-.ete`r p-pey,'threads. A

Y .'Thefgaugeqmaylhe..fastenedrgdly onto ja ThisY complished, amongothers, the objects hereinbefore referred to.

As lmany changes could be made in the f above yconstruction zand -manyapparently :guageused in the following claims is intended to cover allof the generic and specific features `of the `invention Vvherein 'de`scribed and all statements of the'scope of the invention which, as amatter of'language, might be said to Vfall therebetween.

I claim as my invention:

- 1. In a gauge, a body, a rest thereon, and apair of gauge members, oneon either side Vof and spaced from said rest member-and provided withconverging serrated Vfaces to receive a tapered thread. Y

2. In a gauge, aV body, a rest thereon,and a pair of gaugemembers, oneon either side of and spaced from said rest member and having convergingserrated faces to receive a'tapered thread, .one of said serrated facesbeing graduated to indicate tolerance limits.

3. In a gauge, a body, a. rest thereon, and a pairof gauge members, oneoneither side of and spaced from said rest member, .said gauge Ymembershavingv converging .serrated contact faces to receive a tapered threadand means to hold said gauge members against .movement in alldirections.

v 4.. In a gauge, a body vportion having a recess and a pair of grooved.facesradiating from .said recess at oppositesidesthereof, a gaugemember in the groove of'each of said faces, screws for holding said,gauge members against the bottoms .of Asaid, grooves,

' holdingrthemv in adjusted position.

5. In a gauge, ay body, a restthereon, and

Ava. pair of gauge members one. on either .side

of and spaced more than 90 from said rest member, said gauge members.having serrated gauge faces.`

6. YIn agange, a body, a. restthereon, and a pair of gauge members,one'on either side and spacedfrom said rest member and providedwith.fserrations inclined to a plane to which the axis of a lthreadedmember positioned Vbetween said j gauge members is kper- .penjdicularSOas to'jco'rrespondwith Ythe thread of the memberb'eing gau'ged 7.lIna'gauge, :a'body, arest thereon, .a

jpair'lofggauge members, one 'oneither`l of and spaced vfrom 'said restynigeriather,eend

justing means for said gauge members to pair of gauge members, one oneither side of center them With respect to said rest comand spaced fromsaid rest member, screws prising screws holding said gauge membersholding said gauge members to said body, 10 to said body and screwsarranged to hold screws holding saidY gauge members against 5 said gaugemembers against longitudinal Vlongitudinal movement, and means to holdmovement. n said gauge members against rotation.

8. In a gauge, a body, a rest thereon, a BENGT M. W. HANSON.

